This invention relates to an automatic performance device which automatically produces tones of rhythm musical instruments such as drums and cymbals, or tones of musical scale as accompaniment by bass tones, chord tones or arpeggio tones played on the keyboard.
An automatic performance device is well known in the art, in which a plurality of performance patterns (a rhythm section pattern, a bass pattern, a chord pattern and an arpeggio pattern) are stored in a pattern memory corresponding to various rhythms, a desired performance pattern (consisting of specific pattern pulses) corresponding to a specified rhythm is read out of the pattern memory by utilizing as an address generator a tempo counter driven by a tempo pulse in accordance with a rhythm specifying signal from a rhythm selection switch, and various rhythm tone generators, an automatic bass chord performance unit or an automatic arpeggio performance unit are controlled according to the performance pattern thus read, thereby to automatically perform rhythm section tones, bass tones, chord tones or arpeggio tones.
In the conventional automatic performance device, a performance pattern read out of the pattern memory is determined by the rhythm specifying signal provided by the rhythm selection, the pattern memory stores patterns for only two measures at maximum because of its capacity, and it is difficult to change the rhythm specifying signal by operating the rhythm selection switch during the performance. Therefore, if a rhythm is determined by the rhythm specifying signal, then the performance pattern corresponding to the rhythm thus determined is merely repeated every two measures. Thus, the automatic performance is considerably monotonous.